Call progress tone generation in a communication system

ABSTRACT

A method of operating a wireless calling device comprises connecting to a call tone provider configured to provide call tones, transferring a plurality of call tone requests to the call tone provider, receiving a plurality of call tones from the call tone provider in response to the plurality of call tone requests, transferring a call setup message to a telecommunication switch to initiate a call, receiving a call message from the telecommunication switch in response to the call setup message wherein the call setup message indicates a status of the call, processing the call message to select a one call tone from the plurality of call tones based on the status of the call, and audibly playing the one call tone.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/343,722, that was filed on Jan. 31, 2006; that is titled “CALLPROGRESS TONE GENERATION IN A COMMUNICATION SYSTEM;” and that is herebyincorporated by reference into this patent application; and which is acontinuation of U.S. patent application Ser. No. 10/103,576 filed Mar.21, 2002; that is titled “CALL PROGRESS TONE GENERATION IN ACOMMUNICATION SYSTEM”; and that is hereby incorporated by reference intothis patent application.

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

MICROFICHE APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the field of communication systems, and moreparticularly, to calling devices that generate and play call progresstones.

2. Description of the Prior Art

When making a call, a caller may hear tones or message being played thatindicate the status of a call. The tones are commonly referred to ascall progress tones (CPT), which are audible tones or messages played toindicate the progress of a call. One example of a call progress tone isa slow busy signal that indicates that the called party is notavailable. Another example of a call progress tone is a fast busy signalthat indicates that the system is busy. Another example of a callprogress tone is a message stating that the line is busy.

A typical communication system is comprised of a calling device coupledto an originating system. The originating system is coupled to a PublicSwitched Telephone Network (PSTN). Examples of calling devices aretelephones, cellular phones, computers, and fax machines. An example ofthe originating system is a class-5 switch.

A user of the calling device initiates a call to a called device in thePSTN through the originating system. The calling device transmits set upmessages to the originating system. The originating system sets up thecall by exchanging signaling with a terminating system connected to thecalled device. The terminating system transmits acknowledgment messagesto the originating system to indicate the progress of the call. Theacknowledgment messages inform the originating system whether the callcan be completed. For instance, the acknowledgment messages indicatethat the PSTN is busy, that the called device is busy, that the calleddevice is being alerted, or some other event. The originating systemprocesses the acknowledgment messages to determine the proper callprogress tone for the call. The originating system generates andtransmits the call progress tone to the calling device. The callingdevice plays audible sounds that represent the call progress tone sothat the user of the calling device can hear it.

Unfortunately, the originating system generates the call progress tonesand maintains the call to transmit the call progress tones, whichincreases the workload on the originating system. Consequently, theoriginating system does not effectively handle other calls, which couldadversely affect the performance of the communication system.

This can be a particular problem in wireless networks. The originatingsystem transmits the call progress tones over a frequency to a wirelessphone. Frequencies and bandwidth are valuable commodities in a wirelessnetwork, and the originating system uses valuable bandwidth to transmitthe call progress tones.

SUMMARY OF THE INVENTION

In an embodiment of the invention, a method of operating a wirelesscalling device comprises connecting to a call tone provider configuredto provide call tones, transferring a plurality of call tone requests tothe call tone provider, receiving a plurality of call tones from thecall tone provider in response to the plurality of call tone requests,transferring a call setup message to a telecommunication switch toinitiate a call, receiving a call message from the telecommunicationswitch in response to the call setup message wherein the call setupmessage indicates a status of the call, processing the call message toselect a one call tone from the plurality of call tones based on thestatus of the call, and audibly playing the one call tone.

BRIEF DESCRIPTION OF THE DRAWINGS

The appended claims set forth the features of the present invention withparticularity. The invention, together with its advantages, may be bestunderstood from the following detailed description taken in conjunctionwith the accompanying drawings:

FIG. 1 is a block diagram that depicts a communication system in theprior art;

FIG. 2 is a signal diagram for the communication system in FIG. 1 in theprior art;

FIG. 3 is a block diagram that depicts a communication system in anexample of the invention;

FIG. 4 is a signal diagram for the communication system in FIG. 3 in anexample of the invention;

FIG. 5 is a block diagram that depicts a communication system wherein acalling device has a wireline connection with a switch in an example ofthe invention;

FIG. 6 is a block diagram that depicts a communication system wherein acalling device has with a wireless connection with a switch in anexample of the invention;

FIG. 7 is a signal diagram for the communication systems in FIGS. 5 and6 in an example of the invention;

FIG. 8 is a flow diagram of a process executed by a switch to providecall progress tones in an example of the invention;

FIG. 9 is a flow diagram of a process executed by a calling device toprovide call progress tones in an example of the invention;

FIG. 10 is a block diagram that depicts a switch in an example of theinvention;

FIG. 11 is a block diagram that depicts a calling device in an exampleof the invention;

FIG. 12 is a flow diagram of a process executed by a calling device toupdate a call progress tone table in an example of the invention; and

FIG. 13 is a flow diagram of a process executed by a switch to update acalling device database in an example of the invention.

DETAILED DESCRIPTION OF THE INVENTION Prior Art CommunicationSystem—FIGS. 1-2

FIG. 1 illustrates communication system 100 in the prior art.Communication system 100 comprises a calling device 102, an originatingsystem 104, and a terminating system 106. Calling device 102 is anydevice configured to play audible sounds that represent call progresstones (CPT). Originating system 104 is any system configured to set upand maintain a call.

FIG. 2 illustrates a signal diagram for communication system 100.Calling device 102 initiates a call to terminating system 106 throughoriginating system 104. Calling device 102 transmits a first set upmessage to originating system 104. Originating system 104 processes thefirst set up message and generates a second set up message. Originatingsystem 104 transmits the second set up message to terminating system106. Originating system 104 receives an acknowledgment (ACK) messagefrom terminating system 106. The acknowledgment message indicates theprogress of the call. Originating system 104 processes theacknowledgment message to determine a call progress tone. Call progresstones are tones or messages that indicate the progress of the call.Originating system 104 generates the call progress tone and transmitsthe call progress tone to calling device 102. Calling device 102 playsaudible sounds that represent the call progress tone. The user ofcalling device 102 can determine the progress of the call by listeningto the call progress tone played by calling device 102. Originatingsystem 104 releases the call if calling device 102 hangs up.

First Embodiment of a Communication System—FIGS. 3-4

FIGS. 3-4 depict a specific example of a communication system in accordwith the present invention. Those skilled in the art will appreciatenumerous variations from this example that do not depart from the scopeof the invention. Those skilled in the art will also appreciate thatvarious features described below could be combined with otherembodiments to form multiple variations of the invention. Those skilledin the art will appreciate that some conventional aspects of FIGS. 3-4have been simplified or omitted for clarity.

FIG. 3 depicts communication system 300 in an example of the invention.Communication system 300 is comprised of calling device 302, originatingsystem 304, and terminating system 306. Calling device 302 is configuredto communicate with originating system 304. Originating system 304 isconfigured to communicate with terminating system 306.

A call typically includes signaling and user communications. Callingdevice 102 is any device capable playing audible sounds that representcall progress tones (CPT). Call progress tones are tones or messagesthat indicate the progress of a call. Originating system 304 is anysystem capable of setting up and maintaining a call. Terminating system306 is any system capable of communicating with originating system 304for a call.

FIG. 4 illustrates a signal diagram for communication system 300 in anexample of the invention. Calling device 302 initiates a call withterminating system 306 through originating system 304. Calling device302 transmits a first set up message to originating system 304.Originating system 304 processes the first set up message and generatesa second set up message. Those skilled in the art will appreciate thatsome conventional steps for setting up and placing a call will not bediscussed for the sake of brevity. Originating system 304 transmits thesecond set up message to terminating system 306.

Originating system 304 then receives an acknowledgment (ACK) messagefrom terminating system 306. Originating system 304 processes theacknowledgment message to generate a call progress message. A callprogress message is any tone, signal, message that indicates the statusof a call. Originating system 304 transmits the call progress message tocalling device 302.

Calling device 302 receives the call progress message. Calling device302 processes the call progress message to determine a call progresstone. Calling device 302 generates the call progress tone and playsaudible sounds that represent the call progress tone.

In this example, calling device 302 advantageously generates the callprogress tone instead of originating system 304. Originating system 304is then able to release the call after transmitting the call progressmessage to calling system 302. Originating system 304 can then handleother calls.

Second Embodiment of a Communication System—FIGS. 5-13

FIGS. 5-13 depict specific examples of a communication system in accordwith the present invention. Those skilled in the art will appreciatenumerous variations from these examples that do not depart from thescope of the invention. Those skilled in the art will also appreciatethat various features described below could be combined with otherembodiments to form multiple variations of the invention. Those skilledin the art will appreciate that some conventional aspects of FIGS. 5-13have been simplified or omitted for clarity.

FIG. 5 depicts an example of communication system 500. Communicationsystem 500 is comprised of calling device 502, switch 504, switch 506,called device 508, and Public Switched Telephone Network (PSTN) 510.Switch 504 includes database 512.

Calling device 502 is configured to communicate with switch 504. In thisexample, calling device 502 communicates with switch 504 over a wirelinelink. Switch 504 is configured to communicate with PSTN 510. Thoseskilled in the art will appreciate that switch 504 communicates withPSTN 510 over a signaling link and a bearer link. PSTN 510 is configuredto communicate with switch 506. Those skilled in the art will appreciatethat switch 506 communicates with PSTN 510 over a signaling link and abearer link. Switch 506 is configured to communicate with called device508. Examples of calling device 502 include, but are not limited to,telephones, computers, and fax machines. Switches 504, 506 compriseconventional switches such as class-5 switches produced by LucentTechnologies.

FIG. 6 depicts another example of communication system 500. In thisexample, calling device 502 communicates with switch 504 over a wirelesslink. The wireless link is facilitated by a tower 612 coupled to a basestation 614. In this example, calling device 502 could be a cellularphone.

To illustrate communication between calling device 502 and switch 504,tower 612 receives wireless signals from calling device 502. Thewireless signals include signaling and user communications. Tower 612and base station 614 function together to convert the wireless signalsinto wireline signals. Base station 614 transfers the wireline signalsto switch 504. Tower 612 and base station 614 function in a similarmanner to receive wireline signals from switch 504, convert the wirelinesignals to wireless signals, and transfer the wireless signals tocalling device 502.

FIG. 7 illustrates a signal diagram of communication system 500 in anexample of the invention. Calling device 502 initiates a call withcalled device 508 through switches 504, 506 and PSTN 510. To initiatethe call, calling device 502 transmits Dual Tone Multi Frequency (DTMF)signaling to switch 504. Examples of signaling include Signaling System7 (SS7) and C7. One skilled in the art will recognize that the followingsteps may involve more signaling depending on the protocol used incommunication system 500. Switch 504 processes the DTMF signaling andgenerates an Initial Address Message (IAM). Switch 504 transmits the IAMto switch 506 over PSTN 510. Switch 506 processes the IAM and generatesan Address Complete Message (ACM). Switch 506 transmits the ACM toswitch 504 over PSTN 510. Those skilled in the art will appreciate thatsome conventional steps for setting up and placing a call will not bediscussed for the sake of brevity.

Switch 504 processes the ACM to generate a call progress message. Switch504 transmits the call progress message to calling device 502. Callingdevice 502 processes the call progress message to determine a callprogress tone. Examples of call progress tones are dial tone, busy tone,ringback tone, error tone, and re-order. Calling device 502 thengenerates the call progress tone and plays audible sounds that representthe call progress tone.

FIG. 8 depicts a process 800 executed by switch 504 to provide callprogress tones for the call in an example of the invention. Switch 504receives the ACM from switch 506. Switch 504 processes the ACM todetermine a proper call progress tone. Switch 504 then determines ifcalling device 502 is configured to generate call progress tones. Tomake this determination, switch 504 searches database 512 for callingdevice 502. Database 512 contains a list of calling devices that areconfigured to generate call progress tones.

If switch 504 does not find calling device 502 in database 512, thenswitch 504 operates in the conventional manner described in the priorart. In the conventional manner, switch 504 generates the proper callprogress tone and transmits the proper call progress tone to callingdevice 502. Switch 504 maintains the call to transmit the proper callprogress tone. Process 800 then ends.

If switch 504 does find calling device 502 in database 512, then switch504 determines if calling device 502 is configured to generate theproper call progress tone. Database 512 lists the call progress tonesthat each calling device can generate. If calling device 502 is notconfigured to generate the proper call progress tone, then switch 504operates in the conventional manner described in the prior art.

If calling device 502 is configured to generate the proper call progresstone, then switch 504 generates a call progress message based on thecall progress tone. Switch 504 transmits the call progress message tocalling device 502. Switch 504 then releases the call. Process 800 thenends. Those skilled in the art will appreciate that calling device 502could also release the call instead of, or in addition to, switch 504.

FIG. 9 depicts a process 900 executed by calling device 502 to generatecall progress tones in an example of the invention. Calling device 502receives the call progress message from switch 504. Calling device 502processes the call progress message and performs a table look-up in acall progress tone table based on the call progress message. If callingdevice 502 locates the call progress message in the call progress tonetable, then calling device 502 determines the proper call progress tonebased on the call progress message. Calling device 502 then generatesthe proper call progress tone and plays audible sounds that representthe proper call progress tone. Process 900 then ends.

If calling device 502 does not locate the call progress message in thecall progress tone table, then calling device 502 determines a defaultcall progress tone. Calling device 502 generates the default callprogress tone and plays audible sounds that represent the proper callprogress tone. Process 900 then ends.

Those skilled in the art will appreciate that the above-described switch504 could be comprised of instructions that are stored on storage media.FIG. 10 shows an example of switch 504. Switch 504 is comprised ofprocessor 1002 and storage media 1004. The instructions can be retrievedand executed by processor 1002. Some examples of instructions aresoftware, program code, and firmware. Some examples of storage media1004 are memory devices, tape, disks, integrated circuits, and servers.The instructions are operational when executed by processor 1002 todirect processor 1002 to operate in accord with the invention. The term“processor” refers to a single processing device or a group ofinter-operational processing devices. Some examples of processor 1002are computers, integrated circuits, and logic circuitry. Those skilledin the art are familiar with instructions, processors, and storagemedia. Switch 504 includes database 512 that could be incorporatedwithin storage media 1004.

Those skilled in the art will also appreciate that the above-describedcalling device 502 could be comprised of instructions that are stored onstorage media. FIG. 11 shows an example of calling device 502. Callingdevice 502 is comprised of processor 1102 and storage media 1104. Theinstructions can be retrieved and executed by processor 1102. Someexamples of instructions are software, program code, and firmware. Someexamples of storage media 1104 are memory devices, tape, disks,integrated circuits, and servers. The instructions are operational whenexecuted by processor 1102 to direct processor 1102 to operate in accordwith the invention. The term “processor” refers to a single processingdevice or a group of inter-operational processing devices. Some examplesof processor 1102 are computers, integrated circuits, and logiccircuitry. Those skilled in the art are familiar with instructions,processors, and storage media. Storage media 1104 could also store calltreatment table 1106 for calling device 502.

The following are exemplary operations of communication system 500 shownin FIG. 5. For a first example, assume that calling device 502 attemptsto place a call to called device 508, and called device 508 is busy.Switch 506 transmits an ACM, that contains a release value denoting thatcalled device 508 was busy, to switch 504. Switch 504 transmits a callprogress message to calling device 502 and then releases the call.Calling device 502 processes the call progress message to determine theproper call progress tone. The proper call progress tone in this case isa slow busy signal. Calling device 502 generates a slow busy signal andplays the audible slow busy signal.

For a second example, assume that calling device 502 attempts to place acall to called device 508, and all trunks between switch 504 and switch506 are busy. Switch 504 determines that the trunks are busy. Switch 504transmits a call progress message to calling device 502 and thenreleases the call. Calling device 502 processes the call progressmessage to determine the proper call progress tone. The proper callprogress tone in this case is a fast busy signal. Calling device 502generates a fast busy signal and plays the audible fast busy signal.

FIG. 12 illustrates a process 1200 for installing new call progresstones in calling device 502. Calling device 502 first connects to aprovider that is configured to provide call progress tones. Theconnection could be, for example, to a switch, a signal processor, or aserver. Calling device 502 then requests a new call progress tone.Calling device 502 receives the new call progress tone from theprovider. Calling device 502 updates the call progress tone table byadding the new call progress tone to the call progress tone table.Process 1200 then ends.

FIG. 13 illustrates a process 1300 for updating database 512. Database512 could be updated when a new calling device is added, or when acalling device installs a new call progress tone. In either case, acalling device connects to switch 504. Switch 504 transmits a query tothe calling device for call progress tone information. Switch 504receives a response from the calling device that includes the callprogress tone information. If the calling device is new, then switch 504adds the calling device and the corresponding call progress toneinformation to database 512. If the calling device is not new, thenswitch 504 locates the calling device in database 512 and updates theentry in database 512 with the call progress tone information. Process1300 then ends.

Those skilled in the art will appreciate variations of theabove-described embodiments that fall within the scope of the invention.As a result, the invention is not limited to the specific examples andillustrations discussed above, but only by the following claims andtheir equivalents.

1. A method of operating a wireless calling device, the methodcomprising: connecting to a call tone provider configured to providecall tones; transferring a plurality of call tone requests to the calltone provider; receiving a plurality of call tones from the call toneprovider in response to the plurality of call tone requests;transferring a call setup message to a telecommunication switch toinitiate a call; receiving a call message from the telecommunicationswitch in response to the call setup message wherein the call messageindicates a status of the call; processing the call message to select aone call tone from the plurality of call tones based on the status ofthe call; and audibly playing the one call tone.
 2. The method of claim1 wherein the wireless calling device comprises a wireless telephone. 3.The method of claim 1 wherein the wireless calling device comprises acomputer.
 4. The method of claim 1 wherein the call tone comprises aringback tone.
 5. The method of claim 1 wherein the call tone comprisesa busy tone.
 6. A wireless calling device comprising: an interfaceconfigured to connect to a call tone provider configured to provide calltones, transfer a plurality of call tone requests to the call toneprovider, receive a plurality of call tones from the call tone providerin response to the plurality of call tone requests, transfer a callsetup message to a telecommunication switch to initiate a call, andreceive a call message from the telecommunication switch in response tothe call setup message wherein the call message indicates a status ofthe call; and a processing system coupled to the interface andconfigured to generate the plurality of call tone requests, generate thecall setup message, process the call message to select a one call tonefrom the plurality of call tones based on the status of the call, andaudibly play the one call tone.
 7. The wireless calling device of claim6 wherein the wireless calling device comprises a wireless telephone. 8.The wireless calling device of claim 6 wherein the wireless callingdevice comprises a computer.
 9. The wireless calling device of claim 6wherein the call tone comprises a ringback tone.
 10. The wirelesscalling device of claim 6 wherein the call tone comprises a busy tone.